/**
 * @author mrdoob / http://mrdoob.com/
 */
import * as THREE from './three.js'
THREE.SpriteCanvasMaterial = function ( parameters ) {

  THREE.Material.call( this );

  this.type = 'SpriteCanvasMaterial';

  this.color = new THREE.Color( 0xffffff );
  this.program = function () {};

  this.setValues( parameters );

};

THREE.SpriteCanvasMaterial.prototype = Object.create( THREE.Material.prototype );
THREE.SpriteCanvasMaterial.prototype.constructor = THREE.SpriteCanvasMaterial;
THREE.SpriteCanvasMaterial.prototype.isSpriteCanvasMaterial = true;

THREE.SpriteCanvasMaterial.prototype.clone = function () {

  var material = new THREE.SpriteCanvasMaterial();

  material.copy( this );
  material.color.copy( this.color );
  material.program = this.program;

  return material;

};

//

THREE.CanvasRenderer = function ( parameters ) {

  console.log( 'THREE.CanvasRenderer', THREE.REVISION );

  parameters = parameters || {};

  var _this = this,
    _renderData, _elements, _lights,
    _projector = new THREE.Projector(),

    _canvas = parameters.canvas !== undefined
      ? parameters.canvas
      : document.createElement( 'canvas' ),

    _canvasWidth = _canvas.width,
    _canvasHeight = _canvas.height,
    _canvasWidthHalf = Math.floor( _canvasWidth / 2 ),
    _canvasHeightHalf = Math.floor( _canvasHeight / 2 ),

    _viewportX = 0,
    _viewportY = 0,
    _viewportWidth = _canvasWidth,
    _viewportHeight = _canvasHeight,

    _pixelRatio = 1,

    _context = _canvas.getContext( '2d', {
      alpha: parameters.alpha === true
    } ),

    _clearColor = new THREE.Color( 0x000000 ),
    _clearAlpha = parameters.alpha === true ? 0 : 1,

    _contextGlobalAlpha = 1,
    _contextGlobalCompositeOperation = 0,
    _contextStrokeStyle = null,
    _contextFillStyle = null,
    _contextLineWidth = null,
    _contextLineCap = null,
    _contextLineJoin = null,
    _contextLineDash = [],

    _v1, _v2, _v3,

    _v1x, _v1y, _v2x, _v2y, _v3x, _v3y,

    _color = new THREE.Color(),

    _diffuseColor = new THREE.Color(),
    _emissiveColor = new THREE.Color(),

    _lightColor = new THREE.Color(),

    _patterns = {},

    _uvs,
    _uv1x, _uv1y, _uv2x, _uv2y, _uv3x, _uv3y,

    _clipBox = new THREE.Box2(),
    _clearBox = new THREE.Box2(),
    _elemBox = new THREE.Box2(),

    _ambientLight = new THREE.Color(),
    _directionalLights = new THREE.Color(),
    _pointLights = new THREE.Color(),

    _vector3 = new THREE.Vector3(), // Needed for PointLight
    _centroid = new THREE.Vector3(),
    _normal = new THREE.Vector3(),
    _normalViewMatrix = new THREE.Matrix3();

  /* TODO
   _canvas.mozImageSmoothingEnabled = false;
   _canvas.webkitImageSmoothingEnabled = false;
   _canvas.msImageSmoothingEnabled = false;
   _canvas.imageSmoothingEnabled = false;
   */

  // dash+gap fallbacks for Firefox and everything else

  if ( _context.setLineDash === undefined ) {

    _context.setLineDash = function () {};

  }

  this.domElement = _canvas;

  this.autoClear = true;
  this.sortObjects = true;
  this.sortElements = true;

  this.info = {

    render: {

      vertices: 0,
      faces: 0

    }

  };

  // WebGLRenderer compatibility

  this.supportsVertexTextures = function () {};
  this.setFaceCulling = function () {};

  // API

  this.getContext = function () {

    return _context;

  };

  this.getContextAttributes = function () {

    return _context.getContextAttributes();

  };

  this.getPixelRatio = function () {

    return _pixelRatio;

  };

  this.setPixelRatio = function ( value ) {

    if ( value !== undefined ) _pixelRatio = value;

  };

  this.setSize = function ( width, height, updateStyle ) {

    _canvasWidth = width * _pixelRatio;
    _canvasHeight = height * _pixelRatio;

    _canvas.width = _canvasWidth;
    _canvas.height = _canvasHeight;

    _canvasWidthHalf = Math.floor( _canvasWidth / 2 );
    _canvasHeightHalf = Math.floor( _canvasHeight / 2 );

    if ( updateStyle !== false ) {

      _canvas.style.width = width + 'px';
      _canvas.style.height = height + 'px';

    }

    _clipBox.min.set( - _canvasWidthHalf, - _canvasHeightHalf );
    _clipBox.max.set(   _canvasWidthHalf,   _canvasHeightHalf );

    _clearBox.min.set( - _canvasWidthHalf, - _canvasHeightHalf );
    _clearBox.max.set(   _canvasWidthHalf,   _canvasHeightHalf );

    _contextGlobalAlpha = 1;
    _contextGlobalCompositeOperation = 0;
    _contextStrokeStyle = null;
    _contextFillStyle = null;
    _contextLineWidth = null;
    _contextLineCap = null;
    _contextLineJoin = null;

    this.setViewport( 0, 0, width, height );

  };

  this.setViewport = function ( x, y, width, height ) {

    _viewportX = x * _pixelRatio;
    _viewportY = y * _pixelRatio;

    _viewportWidth = width * _pixelRatio;
    _viewportHeight = height * _pixelRatio;

  };

  this.setScissor = function () {};
  this.setScissorTest = function () {};

  this.setClearColor = function ( color, alpha ) {

    _clearColor.set( color );
    _clearAlpha = alpha !== undefined ? alpha : 1;

    _clearBox.min.set( - _canvasWidthHalf, - _canvasHeightHalf );
    _clearBox.max.set(   _canvasWidthHalf,   _canvasHeightHalf );

  };

  this.setClearColorHex = function ( hex, alpha ) {

    console.warn( 'THREE.CanvasRenderer: .setClearColorHex() is being removed. Use .setClearColor() instead.' );
    this.setClearColor( hex, alpha );

  };

  this.getClearColor = function () {

    return _clearColor;

  };

  this.getClearAlpha = function () {

    return _clearAlpha;

  };

  this.getMaxAnisotropy = function () {

    return 0;

  };

  this.clear = function () {

    if ( _clearBox.isEmpty() === false ) {

      _clearBox.intersect( _clipBox );
      _clearBox.expandByScalar( 2 );

      _clearBox.min.x =   _clearBox.min.x + _canvasWidthHalf;
      _clearBox.min.y = - _clearBox.min.y + _canvasHeightHalf;		// higher y value !
      _clearBox.max.x =   _clearBox.max.x + _canvasWidthHalf;
      _clearBox.max.y = - _clearBox.max.y + _canvasHeightHalf;		// lower y value !

      if ( _clearAlpha < 1 ) {

        _context.clearRect(
          _clearBox.min.x | 0,
          _clearBox.max.y | 0,
          ( _clearBox.max.x - _clearBox.min.x ) | 0,
          ( _clearBox.min.y - _clearBox.max.y ) | 0
        );

      }

      if ( _clearAlpha > 0 ) {

        setOpacity( 1 );
        setBlending( THREE.NormalBlending );

        setFillStyle( 'rgba(' + Math.floor( _clearColor.r * 255 ) + ',' + Math.floor( _clearColor.g * 255 ) + ',' + Math.floor( _clearColor.b * 255 ) + ',' + _clearAlpha + ')' );

        _context.fillRect(
          _clearBox.min.x | 0,
          _clearBox.max.y | 0,
          ( _clearBox.max.x - _clearBox.min.x ) | 0,
          ( _clearBox.min.y - _clearBox.max.y ) | 0
        );

      }

      _clearBox.makeEmpty();

    }

  };

  // compatibility

  this.clearColor = function () {};
  this.clearDepth = function () {};
  this.clearStencil = function () {};

  this.render = function ( scene, camera ) {

    if ( camera.isCamera === undefined ) {

      console.error( 'THREE.CanvasRenderer.render: camera is not an instance of THREE.Camera.' );
      return;

    }

    var background = scene.background;

    if ( background && background.isColor ) {

      setOpacity( 1 );
      setBlending( THREE.NormalBlending );

      setFillStyle( background.getStyle() );
      _context.fillRect( 0, 0, _canvasWidth, _canvasHeight );

    } else if ( this.autoClear === true ) {

      this.clear();

    }

    _this.info.render.vertices = 0;
    _this.info.render.faces = 0;

    _context.setTransform( _viewportWidth / _canvasWidth, 0, 0, - _viewportHeight / _canvasHeight, _viewportX, _canvasHeight - _viewportY );
    _context.translate( _canvasWidthHalf, _canvasHeightHalf );

    _renderData = _projector.projectScene( scene, camera, this.sortObjects, this.sortElements );
    _elements = _renderData.elements;
    _lights = _renderData.lights;

    _normalViewMatrix.getNormalMatrix( camera.matrixWorldInverse );

    /* DEBUG
     setFillStyle( 'rgba( 0, 255, 255, 0.5 )' );
     _context.fillRect( _clipBox.min.x, _clipBox.min.y, _clipBox.max.x - _clipBox.min.x, _clipBox.max.y - _clipBox.min.y );
     */

    calculateLights();

    for ( var e = 0, el = _elements.length; e < el; e ++ ) {

      var element = _elements[ e ];

      var material = element.material;

      if ( material === undefined || material.opacity === 0 ) continue;

      _elemBox.makeEmpty();

      if ( element instanceof THREE.RenderableSprite ) {

        _v1 = element;
        _v1.x *= _canvasWidthHalf; _v1.y *= _canvasHeightHalf;

        renderSprite( _v1, element, material );

      } else if ( element instanceof THREE.RenderableLine ) {

        _v1 = element.v1; _v2 = element.v2;

        _v1.positionScreen.x *= _canvasWidthHalf; _v1.positionScreen.y *= _canvasHeightHalf;
        _v2.positionScreen.x *= _canvasWidthHalf; _v2.positionScreen.y *= _canvasHeightHalf;

        _elemBox.setFromPoints( [
          _v1.positionScreen,
          _v2.positionScreen
        ] );

        if ( _clipBox.intersectsBox( _elemBox ) === true ) {

          renderLine( _v1, _v2, element, material );

        }

      } else if ( element instanceof THREE.RenderableFace ) {

        _v1 = element.v1; _v2 = element.v2; _v3 = element.v3;

        if ( _v1.positionScreen.z < - 1 || _v1.positionScreen.z > 1 ) continue;
        if ( _v2.positionScreen.z < - 1 || _v2.positionScreen.z > 1 ) continue;
        if ( _v3.positionScreen.z < - 1 || _v3.positionScreen.z > 1 ) continue;

        _v1.positionScreen.x *= _canvasWidthHalf; _v1.positionScreen.y *= _canvasHeightHalf;
        _v2.positionScreen.x *= _canvasWidthHalf; _v2.positionScreen.y *= _canvasHeightHalf;
        _v3.positionScreen.x *= _canvasWidthHalf; _v3.positionScreen.y *= _canvasHeightHalf;

        if ( material.overdraw > 0 ) {

          expand( _v1.positionScreen, _v2.positionScreen, material.overdraw );
          expand( _v2.positionScreen, _v3.positionScreen, material.overdraw );
          expand( _v3.positionScreen, _v1.positionScreen, material.overdraw );

        }

        _elemBox.setFromPoints( [
          _v1.positionScreen,
          _v2.positionScreen,
          _v3.positionScreen
        ] );

        if ( _clipBox.intersectsBox( _elemBox ) === true ) {

          renderFace3( _v1, _v2, _v3, 0, 1, 2, element, material );

        }

      }

      /* DEBUG
       setLineWidth( 1 );
       setStrokeStyle( 'rgba( 0, 255, 0, 0.5 )' );
       _context.strokeRect( _elemBox.min.x, _elemBox.min.y, _elemBox.max.x - _elemBox.min.x, _elemBox.max.y - _elemBox.min.y );
       */

      _clearBox.union( _elemBox );

    }

    /* DEBUG
     setLineWidth( 1 );
     setStrokeStyle( 'rgba( 255, 0, 0, 0.5 )' );
     _context.strokeRect( _clearBox.min.x, _clearBox.min.y, _clearBox.max.x - _clearBox.min.x, _clearBox.max.y - _clearBox.min.y );
     */

    _context.setTransform( 1, 0, 0, 1, 0, 0 );

  };

  //

  function calculateLights() {

    _ambientLight.setRGB( 0, 0, 0 );
    _directionalLights.setRGB( 0, 0, 0 );
    _pointLights.setRGB( 0, 0, 0 );

    for ( var l = 0, ll = _lights.length; l < ll; l ++ ) {

      var light = _lights[ l ];
      var lightColor = light.color;

      if ( light.isAmbientLight ) {

        _ambientLight.add( lightColor );

      } else if ( light.isDirectionalLight ) {

        // for sprites

        _directionalLights.add( lightColor );

      } else if ( light.isPointLight ) {

        // for sprites

        _pointLights.add( lightColor );

      }

    }

  }

  function calculateLight( position, normal, color ) {

    for ( var l = 0, ll = _lights.length; l < ll; l ++ ) {

      var light = _lights[ l ];

      _lightColor.copy( light.color );

      if ( light.isDirectionalLight ) {

        var lightPosition = _vector3.setFromMatrixPosition( light.matrixWorld ).normalize();

        var amount = normal.dot( lightPosition );

        if ( amount <= 0 ) continue;

        amount *= light.intensity;

        color.add( _lightColor.multiplyScalar( amount ) );

      } else if ( light.isPointLight ) {

        var lightPosition = _vector3.setFromMatrixPosition( light.matrixWorld );

        var amount = normal.dot( _vector3.subVectors( lightPosition, position ).normalize() );

        if ( amount <= 0 ) continue;

        amount *= light.distance == 0 ? 1 : 1 - Math.min( position.distanceTo( lightPosition ) / light.distance, 1 );

        if ( amount == 0 ) continue;

        amount *= light.intensity;

        color.add( _lightColor.multiplyScalar( amount ) );

      }

    }

  }

  function renderSprite( v1, element, material ) {

    setOpacity( material.opacity );
    setBlending( material.blending );

    var scaleX = element.scale.x * _canvasWidthHalf;
    var scaleY = element.scale.y * _canvasHeightHalf;

    var dist = Math.sqrt( scaleX * scaleX + scaleY * scaleY ); // allow for rotated sprite
    _elemBox.min.set( v1.x - dist, v1.y - dist );
    _elemBox.max.set( v1.x + dist, v1.y + dist );

    if ( material.isSpriteMaterial ) {

      var texture = material.map;

      if ( texture !== null ) {

        var pattern = _patterns[ texture.id ];

        if ( pattern === undefined || pattern.version !== texture.version ) {

          pattern = textureToPattern( texture );
          _patterns[ texture.id ] = pattern;

        }

        if ( pattern.canvas !== undefined ) {

          setFillStyle( pattern.canvas );

          var bitmap = texture.image;

          var ox = bitmap.width * texture.offset.x;
          var oy = bitmap.height * texture.offset.y;

          var sx = bitmap.width * texture.repeat.x;
          var sy = bitmap.height * texture.repeat.y;

          var cx = scaleX / sx;
          var cy = scaleY / sy;

          _context.save();
          _context.translate( v1.x, v1.y );
          if ( material.rotation !== 0 ) _context.rotate( material.rotation );
          _context.translate( - scaleX / 2, - scaleY / 2 );
          _context.scale( cx, cy );
          _context.translate( - ox, - oy );
          _context.fillRect( ox, oy, sx, sy );
          _context.restore();

        }

      } else {

        // no texture

        setFillStyle( material.color.getStyle() );

        _context.save();
        _context.translate( v1.x, v1.y );
        if ( material.rotation !== 0 ) _context.rotate( material.rotation );
        _context.scale( scaleX, - scaleY );
        _context.fillRect( - 0.5, - 0.5, 1, 1 );
        _context.restore();

      }

    } else if ( material.isSpriteCanvasMaterial ) {

      setStrokeStyle( material.color.getStyle() );
      setFillStyle( material.color.getStyle() );

      _context.save();
      _context.translate( v1.x, v1.y );
      if ( material.rotation !== 0 ) _context.rotate( material.rotation );
      _context.scale( scaleX, scaleY );

      material.program( _context );

      _context.restore();

    } else if ( material.isPointsMaterial ) {

      setFillStyle( material.color.getStyle() );

      _context.save();
      _context.translate( v1.x, v1.y );
      if ( material.rotation !== 0 ) _context.rotate( material.rotation );
      _context.scale( scaleX * material.size, - scaleY * material.size );
      _context.fillRect( - 0.5, - 0.5, 1, 1 );
      _context.restore();

    }

    /* DEBUG
     setStrokeStyle( 'rgb(255,255,0)' );
     _context.beginPath();
     _context.moveTo( v1.x - 10, v1.y );
     _context.lineTo( v1.x + 10, v1.y );
     _context.moveTo( v1.x, v1.y - 10 );
     _context.lineTo( v1.x, v1.y + 10 );
     _context.stroke();
     */

  }

  function renderLine( v1, v2, element, material ) {

    setOpacity( material.opacity );
    setBlending( material.blending );

    _context.beginPath();
    _context.moveTo( v1.positionScreen.x, v1.positionScreen.y );
    _context.lineTo( v2.positionScreen.x, v2.positionScreen.y );

    if ( material.isLineBasicMaterial ) {

      setLineWidth( material.linewidth );
      setLineCap( material.linecap );
      setLineJoin( material.linejoin );

      if ( material.vertexColors !== THREE.VertexColors ) {

        setStrokeStyle( material.color.getStyle() );

      } else {

        var colorStyle1 = element.vertexColors[ 0 ].getStyle();
        var colorStyle2 = element.vertexColors[ 1 ].getStyle();

        if ( colorStyle1 === colorStyle2 ) {

          setStrokeStyle( colorStyle1 );

        } else {

          try {

            var grad = _context.createLinearGradient(
              v1.positionScreen.x,
              v1.positionScreen.y,
              v2.positionScreen.x,
              v2.positionScreen.y
            );
            grad.addColorStop( 0, colorStyle1 );
            grad.addColorStop( 1, colorStyle2 );

          } catch ( exception ) {

            grad = colorStyle1;

          }

          setStrokeStyle( grad );

        }

      }

      if ( material.isLineDashedMaterial ) {

        setLineDash( [ material.dashSize, material.gapSize ] );

      }

      _context.stroke();
      _elemBox.expandByScalar( material.linewidth * 2 );

      if ( material.isLineDashedMaterial ) {

        setLineDash( [] );

      }

    }

  }

  function renderFace3( v1, v2, v3, uv1, uv2, uv3, element, material ) {

    _this.info.render.vertices += 3;
    _this.info.render.faces ++;

    setOpacity( material.opacity );
    setBlending( material.blending );

    _v1x = v1.positionScreen.x; _v1y = v1.positionScreen.y;
    _v2x = v2.positionScreen.x; _v2y = v2.positionScreen.y;
    _v3x = v3.positionScreen.x; _v3y = v3.positionScreen.y;

    drawTriangle( _v1x, _v1y, _v2x, _v2y, _v3x, _v3y );

    if ( ( material.isMeshLambertMaterial || material.isMeshPhongMaterial || material.isMeshStandardMaterial ) && material.map === null ) {

      _diffuseColor.copy( material.color );
      _emissiveColor.copy( material.emissive );

      if ( material.vertexColors === THREE.FaceColors ) {

        _diffuseColor.multiply( element.color );

      }

      _color.copy( _ambientLight );

      _centroid.copy( v1.positionWorld ).add( v2.positionWorld ).add( v3.positionWorld ).divideScalar( 3 );

      calculateLight( _centroid, element.normalModel, _color );

      _color.multiply( _diffuseColor ).add( _emissiveColor );

      material.wireframe === true
        ? strokePath( _color, material.wireframeLinewidth, material.wireframeLinecap, material.wireframeLinejoin )
        : fillPath( _color );

    } else if ( material.isMeshBasicMaterial || material.isMeshLambertMaterial || material.isMeshPhongMaterial || material.isMeshStandardMaterial ) {

      if ( material.map !== null ) {

        var mapping = material.map.mapping;

        if ( mapping === THREE.UVMapping ) {

          _uvs = element.uvs;
          patternPath( _v1x, _v1y, _v2x, _v2y, _v3x, _v3y, _uvs[ uv1 ].x, _uvs[ uv1 ].y, _uvs[ uv2 ].x, _uvs[ uv2 ].y, _uvs[ uv3 ].x, _uvs[ uv3 ].y, material.map );

        }

      } else if ( material.envMap !== null ) {

        if ( material.envMap.mapping === THREE.SphericalReflectionMapping ) {

          _normal.copy( element.vertexNormalsModel[ uv1 ] ).applyMatrix3( _normalViewMatrix );
          _uv1x = 0.5 * _normal.x + 0.5;
          _uv1y = 0.5 * _normal.y + 0.5;

          _normal.copy( element.vertexNormalsModel[ uv2 ] ).applyMatrix3( _normalViewMatrix );
          _uv2x = 0.5 * _normal.x + 0.5;
          _uv2y = 0.5 * _normal.y + 0.5;

          _normal.copy( element.vertexNormalsModel[ uv3 ] ).applyMatrix3( _normalViewMatrix );
          _uv3x = 0.5 * _normal.x + 0.5;
          _uv3y = 0.5 * _normal.y + 0.5;

          patternPath( _v1x, _v1y, _v2x, _v2y, _v3x, _v3y, _uv1x, _uv1y, _uv2x, _uv2y, _uv3x, _uv3y, material.envMap );

        }

      } else {

        _color.copy( material.color );

        if ( material.vertexColors === THREE.FaceColors ) {

          _color.multiply( element.color );

        }

        material.wireframe === true
          ? strokePath( _color, material.wireframeLinewidth, material.wireframeLinecap, material.wireframeLinejoin )
          : fillPath( _color );

      }

    } else if ( material.isMeshNormalMaterial ) {

      _normal.copy( element.normalModel ).applyMatrix3( _normalViewMatrix );

      _color.setRGB( _normal.x, _normal.y, _normal.z ).multiplyScalar( 0.5 ).addScalar( 0.5 );

      material.wireframe === true
        ? strokePath( _color, material.wireframeLinewidth, material.wireframeLinecap, material.wireframeLinejoin )
        : fillPath( _color );

    } else {

      _color.setRGB( 1, 1, 1 );

      material.wireframe === true
        ? strokePath( _color, material.wireframeLinewidth, material.wireframeLinecap, material.wireframeLinejoin )
        : fillPath( _color );

    }

  }

  //

  function drawTriangle( x0, y0, x1, y1, x2, y2 ) {

    _context.beginPath();
    _context.moveTo( x0, y0 );
    _context.lineTo( x1, y1 );
    _context.lineTo( x2, y2 );
    _context.closePath();

  }

  function strokePath( color, linewidth, linecap, linejoin ) {

    setLineWidth( linewidth );
    setLineCap( linecap );
    setLineJoin( linejoin );
    setStrokeStyle( color.getStyle() );

    _context.stroke();

    _elemBox.expandByScalar( linewidth * 2 );

  }

  function fillPath( color ) {

    setFillStyle( color.getStyle() );
    _context.fill();

  }

  function textureToPattern( texture ) {

    if ( texture.version === 0 ||
      texture instanceof THREE.CompressedTexture ||
      texture instanceof THREE.DataTexture ) {

      return {
        canvas: undefined,
        version: texture.version
      };

    }

    var image = texture.image;

    if ( image.complete === false ) {

      return {
        canvas: undefined,
        version: 0
      };

    }

    var repeatX = texture.wrapS === THREE.RepeatWrapping || texture.wrapS === THREE.MirroredRepeatWrapping;
    var repeatY = texture.wrapT === THREE.RepeatWrapping || texture.wrapT === THREE.MirroredRepeatWrapping;

    var mirrorX = texture.wrapS === THREE.MirroredRepeatWrapping;
    var mirrorY = texture.wrapT === THREE.MirroredRepeatWrapping;

    //

    var canvas = document.createElement( 'canvas' );
    canvas.width = image.width * ( mirrorX ? 2 : 1 );
    canvas.height = image.height * ( mirrorY ? 2 : 1 );

    var context = canvas.getContext( '2d' );
    context.setTransform( 1, 0, 0, - 1, 0, image.height );
    context.drawImage( image, 0, 0 );

    if ( mirrorX === true ) {

      context.setTransform( - 1, 0, 0, - 1, image.width, image.height );
      context.drawImage( image, - image.width, 0 );

    }

    if ( mirrorY === true ) {

      context.setTransform( 1, 0, 0, 1, 0, 0 );
      context.drawImage( image, 0, image.height );

    }

    if ( mirrorX === true && mirrorY === true ) {

      context.setTransform( - 1, 0, 0, 1, image.width, 0 );
      context.drawImage( image, - image.width, image.height );

    }

    var repeat = 'no-repeat';

    if ( repeatX === true && repeatY === true ) {

      repeat = 'repeat';

    } else if ( repeatX === true ) {

      repeat = 'repeat-x';

    } else if ( repeatY === true ) {

      repeat = 'repeat-y';

    }

    var pattern = _context.createPattern( canvas, repeat );

    if ( texture.onUpdate ) texture.onUpdate( texture );

    return {
      canvas: pattern,
      version: texture.version
    };

  }

  function patternPath( x0, y0, x1, y1, x2, y2, u0, v0, u1, v1, u2, v2, texture ) {

    var pattern = _patterns[ texture.id ];

    if ( pattern === undefined || pattern.version !== texture.version ) {

      pattern = textureToPattern( texture );
      _patterns[ texture.id ] = pattern;

    }

    if ( pattern.canvas !== undefined ) {

      setFillStyle( pattern.canvas );

    } else {

      setFillStyle( 'rgba( 0, 0, 0, 1)' );
      _context.fill();
      return;

    }

    // http://extremelysatisfactorytotalitarianism.com/blog/?p=2120

    var a, b, c, d, e, f, det, idet,
      offsetX = texture.offset.x / texture.repeat.x,
      offsetY = texture.offset.y / texture.repeat.y,
      width = texture.image.width * texture.repeat.x,
      height = texture.image.height * texture.repeat.y;

    u0 = ( u0 + offsetX ) * width;
    v0 = ( v0 + offsetY ) * height;

    u1 = ( u1 + offsetX ) * width;
    v1 = ( v1 + offsetY ) * height;

    u2 = ( u2 + offsetX ) * width;
    v2 = ( v2 + offsetY ) * height;

    x1 -= x0; y1 -= y0;
    x2 -= x0; y2 -= y0;

    u1 -= u0; v1 -= v0;
    u2 -= u0; v2 -= v0;

    det = u1 * v2 - u2 * v1;

    if ( det === 0 ) return;

    idet = 1 / det;

    a = ( v2 * x1 - v1 * x2 ) * idet;
    b = ( v2 * y1 - v1 * y2 ) * idet;
    c = ( u1 * x2 - u2 * x1 ) * idet;
    d = ( u1 * y2 - u2 * y1 ) * idet;

    e = x0 - a * u0 - c * v0;
    f = y0 - b * u0 - d * v0;

    _context.save();
    _context.transform( a, b, c, d, e, f );
    _context.fill();
    _context.restore();

  }

  /*
   function clipImage( x0, y0, x1, y1, x2, y2, u0, v0, u1, v1, u2, v2, image ) {

   // http://extremelysatisfactorytotalitarianism.com/blog/?p=2120

   var a, b, c, d, e, f, det, idet,
   width = image.width - 1,
   height = image.height - 1;

   u0 *= width; v0 *= height;
   u1 *= width; v1 *= height;
   u2 *= width; v2 *= height;

   x1 -= x0; y1 -= y0;
   x2 -= x0; y2 -= y0;

   u1 -= u0; v1 -= v0;
   u2 -= u0; v2 -= v0;

   det = u1 * v2 - u2 * v1;

   idet = 1 / det;

   a = ( v2 * x1 - v1 * x2 ) * idet;
   b = ( v2 * y1 - v1 * y2 ) * idet;
   c = ( u1 * x2 - u2 * x1 ) * idet;
   d = ( u1 * y2 - u2 * y1 ) * idet;

   e = x0 - a * u0 - c * v0;
   f = y0 - b * u0 - d * v0;

   _context.save();
   _context.transform( a, b, c, d, e, f );
   _context.clip();
   _context.drawImage( image, 0, 0 );
   _context.restore();

   }
   */

  // Hide anti-alias gaps

  function expand( v1, v2, pixels ) {

    var x = v2.x - v1.x, y = v2.y - v1.y,
      det = x * x + y * y, idet;

    if ( det === 0 ) return;

    idet = pixels / Math.sqrt( det );

    x *= idet; y *= idet;

    v2.x += x; v2.y += y;
    v1.x -= x; v1.y -= y;

  }

  // Context cached methods.

  function setOpacity( value ) {

    if ( _contextGlobalAlpha !== value ) {

      _context.globalAlpha = value;
      _contextGlobalAlpha = value;

    }

  }

  function setBlending( value ) {

    if ( _contextGlobalCompositeOperation !== value ) {

      if ( value === THREE.NormalBlending ) {

        _context.globalCompositeOperation = 'source-over';

      } else if ( value === THREE.AdditiveBlending ) {

        _context.globalCompositeOperation = 'lighter';

      } else if ( value === THREE.SubtractiveBlending ) {

        _context.globalCompositeOperation = 'darker';

      } else if ( value === THREE.MultiplyBlending ) {

        _context.globalCompositeOperation = 'multiply';

      }

      _contextGlobalCompositeOperation = value;

    }

  }

  function setLineWidth( value ) {

    if ( _contextLineWidth !== value ) {

      _context.lineWidth = value;
      _contextLineWidth = value;

    }

  }

  function setLineCap( value ) {

    // "butt", "round", "square"

    if ( _contextLineCap !== value ) {

      _context.lineCap = value;
      _contextLineCap = value;

    }

  }

  function setLineJoin( value ) {

    // "round", "bevel", "miter"

    if ( _contextLineJoin !== value ) {

      _context.lineJoin = value;
      _contextLineJoin = value;

    }

  }

  function setStrokeStyle( value ) {

    if ( _contextStrokeStyle !== value ) {

      _context.strokeStyle = value;
      _contextStrokeStyle = value;

    }

  }

  function setFillStyle( value ) {

    if ( _contextFillStyle !== value ) {

      _context.fillStyle = value;
      _contextFillStyle = value;

    }

  }

  function setLineDash( value ) {

    if ( _contextLineDash.length !== value.length ) {

      _context.setLineDash( value );
      _contextLineDash = value;

    }

  }

};
